The Celtics reached the second round of the 2010-2011 NBA playoffs. They were eliminated by the Miami Heat in the Eastern Conference semifinals.
Yes, they just recently defeated the Knicks in their last series with a sweep 4 games to none.
The Cleveland Cavaliers
The Boston Celtics
As of the end of the 2009 season the last time the Jaguars were in the playoffs was 2007.